stf_zad_ktrl

#include <iostream>
#include <conio.h>

using namespace std;

double input_array(double *array, size_t array_size);
double calculate_average(double *, size_t);
void find_min_positive(double *, size_t, double &, int &);
void output_array(double *array, size_t array_size);

int main() {

    size_t array_size;

    int choice, min_positive_index = 0;

    double min_positive = 0.0;

    cout << "Enter array size: ";
    cin >> array_size;

    if(!cin || array_size < 0 || array_size > 15)
        return 0;

    double *array = new double[array_size];

    do {
        system("cls");
        cout << "Menu: \n";
        cout << "1. Input array\n";
        cout << "2. Average number of negatives in the array\n";
        cout << "3. Find min and its index\n";
        cout << "4. Output array";
        cout << "\n\n0. Exit\n";
        cout << "Enter your choice: ";
        cin >> choice;

        switch(choice) {
        case 1:
            system("cls");
            input_array(array, array_size);
            break;

        case 2:
            system("cls");
            cout << "Average of negative numbers in the array is " << calculate_average(array, array_size);
            _getch();
            break;

        case 3:
            system("cls");
            find_min_positive(array, array_size, min_positive, min_positive_index);
            cout << "Minimum positive is " << min_positive << " and has index #" << min_positive_index;
            _getch();
            break;
        case 4:
            system("cls");
            output_array(array, array_size);
            _getch();
            break;
        }
    } while(choice != 0);

    delete[] array;

    return 0;
}

double input_array(double *array, size_t array_size) {
    for(size_t i = 0; i < array_size; i++) {
        cout << "Enter element #" << i << ": ";
        cin >> array[i];
    }

    return *array;
}

void output_array(double *array, size_t array_size) {
    for(size_t i = 0; i < array_size; i++) {
        cout << array[i] << endl;
    }
}

double calculate_average(double *array, size_t array_size) {
    double average = 0.0;
    int br = 0;

    for(size_t i = 0; i < array_size; i++)
        if(array[i] < 0) {
            average += array[i];
            br++;
        }

    return (average / br);
}

void find_min_positive(double *array, size_t array_size, double &min_positive, int &index) {

    index = 0;
    size_t min_counter = 0;
    size_t min_index = 0;

    for(size_t i = 0; i < array_size; i++)
        if(array[i] > 0) {
            min_counter++;
            min_index = i;
        }

    if(min_counter == 0)
        cout << "No positive numbers";
    else
        min_positive = array[min_index];

    for(size_t i = 0; i < array_size; i++) {
        if(min_positive > array[i] && array[i] > 0) {
            min_positive = array[i];
            index = i+1;
        }
    }
}